2014 NEC Outlook, Part II

Part I of this series reviewed some Code-wide revisions and some of the significant changes in Chapter 1 of the National Electrical Code (NEC). This segment takes a look at some significant revisions in chapters 2 and 3 (with the comment or proposal number cited after each listing). Not all of the 2014 Code changes are presented in this article, and the changes that are covered are provided in the numerical sequence in which they appear in the NEC.

Two new list items have been added to Section 210.8(A). The requirements for ground-fault circuit interrupter protection (GFCI) have been expanded for dwelling units. GFCI protection is now required for receptacles installed within 6 feet of a bathtub or shower stall. Note that this requirement applies to bathtubs or shower stalls, regardless of whether they are in a bathroom or not. In addition, all 125-volt (V), single-phase, 15- and 20-ampere (A) receptacles installed in laundry areas must be GFCI-protected. [ROP 2-46, 2-47; ROC 2-23]

Section 210.8(D) Kitchen Dishwasher Branch Circuit

Requirements for GFCI protection in dwelling unit kitchens have been expanded. A new subdivision (D), “Kitchen Dishwasher Branch Circuit,” has been added to 210.8. Outlets supplying dishwashers are required to be GFCI-protected, which requires a GFCI-protective device installed at the origin of the branch circuit. The reason is related to different end-of-life failure modes and behavior of newer generation dishwashers as compared to the electromechanical units in the past. [ROP 2-5; ROC 2-29]

Section 210.12 Arc-Fault Circuit Interrupter Protection

This section has been revised to require arc-fault circuit interrupters (AFCIs) to be installed in readily accessible locations. Subdivision (A) now recognizes AFCI protection requirements, which have been expanded to kitchens and laundry areas. This expansion of AFCI requirements continues the long-range objective of whole-house AFCI protection in dwelling units that was sought in the original proposals by Consumer Product Safety Commission in the mid-1990s. [ROP 2-80, 2-82a, 2-116, 2-122, 2-124; ROC 2-59]

Section 210.12(A) Dwelling Units

List items (1) through (6) provide the acceptable methods of accomplishing the branch circuit arc-fault protection requirements and associated conditions. This change resulted from a specific fact-finding study and report from Underwriters Laboratories. These new alternatives include use of both circuit-breaker and outlet-device types of AFCI protection in accordance with the specific conditions in each list item. In list items (3) and (4), note that outlet-device AFCI protection is permitted under restrictive conditions that include maximum length of home runs of 50 feet for 14 AWG (15A circuits) and 70 feet for 12 AWG (20A branch circuits. [ROP 2-80, 2-82a, 2-85, 2-92; ROC 2-46, 2-52]

Section 210.12(C) Dormitory Units

A new subdivision (C), “Dormitory Units,” has been added to 210.12. The AFCI protection requirements are expanded to 125V, single-phase, 15- and 20A outlets installed in dormitory unit bedrooms, living rooms, hallways, closets and similar rooms. This new subdivision continues the incremental expansion of AFCI protection for dwelling units, which most dormitories are considered. [ROP2-78; ROC 2-37]

Section 210.13 Ground-Fault Protection of Equipment (GFPE)

A new Section 210.13, “Ground-Fault Protection of Equipment,” has been added to Article 210. The same ground-fault protection for equipment requirements in 230.95 for services and 215.10 for feeders now apply to qualifying branch circuits. [ROP 2-15]

Section 210.17 Electric Vehicle Branch Circuit

A new Section 210.17, “Electric Vehicle Branch Circuit,” has been added to Article 210. This new provision requires any outlet installed for electric vehicle charging loads be provided with a separate (individual) branch circuit. The revision aligns with the load profile requirements for electric vehicle supply equipment (EVSE) and correlates with continuous duty load restrictions included in 210.19(A)(1) and 210.23. [ROP 2-128a]

Section 220.12 Lighting Loads

A new exception has been added to 220.12. Lighting loads are now permitted to be calculated at values specified in an applicable energy code where it is adopted by the jurisdiction. Three conditions of the new exception include monitoring, alarms and not applying demand factors to the general lighting load as provided in 220.42. [ROP 2-228; ROC 2-102, 2-104, 2-106, 2-107, 2-110, 2-111, 2-119a]

240.87 Arc-Energy Reduction

This section is now titled “Arc Energy Reduction” and arranged in a list format. As revised, it now applies to breakers with a highest adjustable trip rating of 1,200A or greater. Subdivision (B) includes new list items (4) and (5), which recognize other methods of arc energy reduction by a specific method, system, equipment or other approved means. [ROP 10-53a; 10-56; ROC 10-24]

Section 250.102(C)(1) and Table 250.102(C)(1)

Table 250.102(C)(1), notes, and informational notes have been added to Part V of Article 250. The new table provides sizes for grounded conductors, main bonding jumpers, supply-side bonding jumpers, and system bonding jumpers and requires using the 12.5 percent rule if exceeding the table values. References in Article 250 have been changed from 250.66 to 250.102(C)(1) and Table 250.102(C)(1). Table 250.66 is now used for sizing only grounding electrode conductors and bonding jumpers in the grounding electrode system. [ROP 5-42; ROC 5-56]

This new section requires a fault current path installed from the source to the service equipment. This means, for grounded systems, a grounded conductor must be installed and routed with the ungrounded conductors to each service disconnecting means. For ungrounded systems, a supply-side bonding jumper must be installed and routed with the ungrounded conductors to each service disconnecting means. [ROP 5-234; ROC 5-101, 5-103]

Chapter 3 Wiring Methods and Materials

Section 310.15(B)(3)(c) and Table 310.15(B)(3)(c)

The word “circular” has been removed from this section and the title of the table. The words “or cables” have been added to this section and in the title of the table. Ambient temperature correction factors in Table 310.15(B)(2)(a) or Table 310.15(B)(2)(b) apply to conductors in raceways and cables on or above rooftops and exposed to direct sunlight. [ROP 6-26, 6-31]

Section 310.15(B)(3)(c) Exception

A new exception has been added following 310.15(B)(3)(c). Ambient temperature correction factors in Table 310.15(B)(2)(a) or Table 310.15(B)(2)(b) do not apply to XHHW-2 insulated conductors in raceways and cables on or above rooftops and exposed to direct sunlight. The new exception is the result of performance testing by both General Cable and Underwriters Laboratories. [ROP 6-41; ROC 6-37]

Section 310.15(B)(7) and Table 310.15(B)(7)

Table 310.15(B)(7) has been deleted, and Section 310.15(B)(7) has been revised and restructured into a list format. An 83 percent multiplier is provided for calculating ampacity for feeders and service conductors supplying dwelling units if the conditions of this section are met. A new informational note references a new Annex (D7) where an example calculation is provided. There are no changes in the reduced ampacity provisions previously included in 310.15(B)(7); it’s just a different way of determining the reduced service and feeder conductor sizes. The same restrictions to dwelling units are still provided in this section as these allowances relate to the load diversity in dwelling units. [ROP 6-49a; ROC 6-52]

Section 314.25 Covers and Canopies

A new last sentence has been added to 314.25. Screws for covers or attaching equipment to boxes shall be compatible and have matching machine threads or be in accordance with the manufacturer’s instructions. Drywall screws and other inappropriate screws are not permitted for use with boxes unless otherwise listed or identified for use with those types. [ROP 9-55]

Section 314.28(A)(3) Smaller Dimensions

A new paragraph has been added to list item (3) addressing conduit body sizes in relation to conductor fill. The new text allows use of conduit bodies smaller than those required in 314.28(A)(2) with conditions. The revision provides a practical allowance for conductor combinations in conduit bodies where marked to indicate suitability for such use. [ROP 9-67; ROC 9-32]

Section 330.10(A)(11) b and c Uses Permitted

List item has been revised to clarify that a corrosion-resistant jacket is required over the metallic covering. The revision aligns this section with UL Standard 1569 Metal Clad Cables. MC cable in wet locations must have a corrosion-resistant jacket as the outer layer of the cable assembly and meet one of a, b or c. [ROP 7-26a, 7-27]

Section 330.30(B) Securing

A new last sentence has been added to 330.30(B). Vertical installations of listed MC cables in sizes 250 kcmil and larger are permitted to be secured at intervals not exceeding 10 feet. Some MC cables are listed and identified for vertical installation where supported at intervals not exceeding 10 feet. [ROP 7-29; ROC 7-5]

Section 330.30(D)(3) MC Cable—Securing and Supporting

A new list item (3) has been added to 330.30(D). Unsupported interlocking armor-type MC cable is permitted in lengths not exceeding 3 feet from the last point where it is securely fastened. This practical relief applies where flexibility is necessary to minimize the transmission of vibration from equipment or to provide flexibility after installation. [ROP 7-31]

Section 338.10(B)(4)(b) Exterior Installations

A new exception has been added following 338.10(B)(4)(b). Underground service-entrance cable is defined in 338.2 and can be a single conductor, or it can be an assembly of multiple conductors. Type USE cable installed as feeders or branch circuits is not subject to the ampacity limitations provided in 340.80. [ROP 7-59; ROC 7-12]

A new last sentence has been added to Exception No. 4 to 348.30(A) and 350.30(A). Listed flexible metal conduit fittings and listed liquidtight flexible metal conduit fittings shall be permitted as a means of support for lengths up to 6 feet. This revision clarifies that, for the purpose of this exception, additional support for flexible metal conduit is not required. [ROP 8-54; ROC 8-11]

Section 376.22(B) Adjustment Factors

This section has been revised by adding the words “at any cross-section of the wireway.” The revised text clarifies that correction factors are not based on the total number of current-­carrying conductors in the wireway exceeding 30. The correction factors apply where the total of current-carrying conductors at any cross-section exceeds 30. [ROP 8-137]

Section 376.56(B)(1) Power Distribution Blocks

List item (1) was revised by adding a second sentence. Power distribution blocks are permitted to be installed on the line side of the service disconnect or the load side. Power distribution blocks installed on the line side of the service equipment shall be listed. [ROP 8-140; ROC 8-43]

Article 393 Low-Voltage Suspended Ceiling Power Distribution Systems

A new Article 393 has been added to NEC Chapter 3 and equips the Code with requirements for new technology DC wiring systems and equipment in the form of suspended ceiling grids. This type of equipment and associated fittings must be listed, driving the requirement for installation instructions. [ROP 18-10a]

Not all of the changes to the NEC are covered in this article. The next part in this series will look at some revisions in chapters 4 through 9.

For complete details about these and other NEC revisions, refer to the NFPA 2014 NEC Report on Proposals and Report on Comments. The terms National Electrical Code and NEC are registered trademarks of the National Fire Protection Association.